import 'package:flutter/cupertino.dart';

class StackPage extends StatelessWidget{
  @override
  Widget build(BuildContext context) {
    Animation widget;

    NotificationListener listener = NotificationListener(child: Container());
    var width = MediaQuery.of(context).size.width;
    return Container(
      height: 500,
      decoration: BoxDecoration(
        color: Color(0xFFFFFFFF),
      ),
      child: Stack(
        alignment:Alignment.topCenter ,
        children: [
          Positioned(
            child: Container(
              decoration: BoxDecoration(
                  color: Color(0x440000ff)
              ),
              height: 300,
              width: width,
            ),
            // height: expandedHeight,
            // top: flexibleSpaceTop,
          ),
          Positioned(
            child: Container(
              decoration: BoxDecoration(
                  color: Color(0x4400ff00)
              ),
              height: 60,
              width: width,
            ),
            height: 60,
            top: 0,
            left: 0,
          ),
          Positioned(
            top: 300.0,
            height: 200,
            left: 0,
            child: Container(
              decoration: BoxDecoration(
                  color: Color(0x44ff0000)
              ),
              height: 200,
              width: width,
            ),
          ),

        ],
      ),
    );
  }

}